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When do we have to use copy constructors?
...ly, this is cached/memoized data accumulated over the object's lifetime in order to speed-up certain slow query operations performed by the object. It is safe to skip copying that data since it will be recalculated when (and if!) the relevant operations are performed. Copying this data may be unjust...
How do I create a crontab through a script
... used to control different cron tasks (control-marker-1, control-marker-2, etc...): (crontab -l 2>/dev/null | grep -v control-marker-1; echo '*/5 * * * * /path/to/job -with args #control-marker-1') | crontab -
– chef
Dec 25 '16 at 10:39
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How to SSH to a VirtualBox guest externally through a host? [closed]
..., I just added additional adapter and it worked, didn't need to edit the /etc/network/interfaces, Thanks!
– brokenfoot
Apr 9 '14 at 23:19
3
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What are the best use cases for Akka framework [closed]
... / HA
Service backend (any industry, any app)
service REST, SOAP, cometd etc
act as message hub / integration layer
scale up, scale out, fault-tolerance / HA
Snap-in concurrency/parallelism ( any app )
Correct
Simple to work with and understand
Just add the jars to your existing JVM project (use...
Why were pandas merges in python faster than data.table merges in R in 2012?
....table has time series merge in mind. Two aspects to that: i) multi column ordered keys such as (id,datetime) ii) fast prevailing join (roll=TRUE) a.k.a. last observation carried forward.
I'll need some time to confirm as it's the first I've seen of the comparison to data.table as presented.
UPD...
Java: using switch statement with enum under subclass
...astically -
public enum Button {
REPORT_ISSUES(0),
CANCEL_ORDER(1),
RETURN_ORDER(2);
private int value;
Button(int value) {
this.value = value;
}
public int getValue() {
return value;
}
}
And the switch...
How would I get a cron job to run every 30 minutes?
... "run when the minute of each hour is 30" (would run at: 1:30, 2:30, 3:30, etc)
example #2
*/30 * * * * your_command
this means "run when the minute of each hour is evenly divisible by 30" (would run at: 1:30, 2:00, 2:30, 3:00, etc)
example #3
0,30 * * * * your_command
this means "run when the...
How do you install Google frameworks (Play, Accounts, etc.) on a Genymotion virtual device? [duplica
I'm currently trying out Genymotion and boy, it's so much faster than the ADT emulator.
10 Answers
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What is the difference between “INNER JOIN” and “OUTER JOIN”?
...great and excellent explanation. but why in column b the values are not in order? i.e it is 6,5 not as 5,6?
– Ameer
Mar 4 '13 at 8:39
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What's the difference between deadlock and livelock?
...k 1
...
Both examples force the threads to aquire the locks in different orders.
While the deadlock waits for the other lock,
the livelock does not really wait - it desperately tries to acquire the lock without the chance of gettin